Using KF as catalyst and tetrahydrofuran as solvent, 5-alkyloxy-3,4-dihalo-2(5H)-furanones was reacted with several aliphatic amines. The chemical structures and absolute configurations of the products were confirmed via rotation, UV-Vis, IR, 1 H NMR, 13 C NMR, MS techniques, elemental analysis and X-ray single crystal diffraction. Thirteen new normal products β-amino-2(5H)-furanones were obtained via the tandem Michael addition-elimination reaction as anticipated in most cases. However, the reaction between the larger steric dicyclohexyl amine and 5-alkyloxy-3,4-dihalo-2(5H)-furanones yielded four new abnormal products, (E)-alkyl 2-halo-4-dicyclohexylamino-4-oxobut-2-enoate. The possible mechanism for the formation of 2(5H)-furanone ring-opening products involving in the rearrangement reaction was proposed. Keywords 5-alkoxy-3,4-dihalo-2(5H)-furanone; aliphatic saturated secondary amine; tandem Michael addition-elinmination reaction; β-amino-2(5H)-furanone; ring-opening rearrangement reaction [9,10] , 特别是 3,4-二卤-2(5H)-呋喃酮与各种含氮 [8,11 ～ 15] 、 硫 [2,16～18] 、磷 [19] 、硒 [20] 等亲核试剂的串联加成-消除反 应, 近年来一直是国内外呋喃酮化学研究热点之一.本工作在前期研究 5-烷氧基-3,4-二卤-2(5H)-呋喃 酮与系列伯胺亲核试剂(如 α,ω-二胺 [11] 、α-氨基酸酯 [12] 、 α-氨基酸 [13] 等)串联迈克尔加成-消除反应反应的基础 上, 进一步研究了苄胺及系列脂肪仲胺与 5-烷氧基-3,4-二卤-2(5H)-呋喃酮的反应(Scheme 1), 对所得产物的单 晶测试等结构表征发现, 除得到与前期研究类似的 β-胺 基-2(5H)-呋喃酮类化合物的正常产物 5a～5l 和 5q～5r 外, 还首次发现有异常的开环产物 5m～5p.

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